IF $\{$

1) Nodes lost their keys that they have used for stored ciphertexts encryption.

OR

2) The encryptor node as the only owner of a primary key was destructed and cannot extract the corresponding plaintexts anymore.

OR

3) There was an emergency condition and access to the key for decryption was time-consuming.

(e.g.,it is likely in healthcare systems or critical infrastructures)

$\}$

THEN $\{$

The intermediary storage (Cloud/Fog/Edge) without the primary secret key reveals the plain message only once for a legitimate or a representative user.

$\}$